Abstract

One of the most important Operations, Administration, and Maintenance
(OAM) capabilities for transport-network operation is fault
localization. An in-service, on-demand path segment monitoring
function of a transport path is indispensable, particularly when the
service monitoring function is activated only between endpoints.
However, the current segment monitoring approach defined for MPLS
(including the MPLS Transport Profile (MPLS-TP)) in RFC 6371
"Operations, Administration, and Maintenance Framework for MPLS-Based
Transport Networks" has drawbacks. This document provides an
analysis of the existing MPLS-TP OAM mechanisms for the path segment
monitoring and provides requirements to guide the development of new
OAM tools to support Hitless Path Segment Monitoring (HPSM).